Good Science and Bad Science And Lack Thereof In Science Fiction Films and TV Series

BAYLOR

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The Earth is in space. It is weightless. The Sun is in space. It is weightless.

I think the term "weightless" is a kind of a human scale evaluation. Since all mass creates the phenomenon of gravity every atom in any object has weight. Every atom in a wrench has weight in relation to the center of mass of the wrench.
Physics is not one of my strong points.:(
 

BigBadBob141

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Your mass remains the same, but your weight depends on the strength of the gravity field you are in.
You weigh less on the Moon and Mars because they are smaller then the Earth, and therefore have less mass, so less gravity!
If you could stand on the surface of the Sun or Jupiter you would be a hell of a lot heavier , your weight would be greater but your mass remains the same!
Another common misconception is that vacuums suck, they don't, it's the other way round, it's the surrounding air which rushes in to fill the vacuum!
There was a flat earther on a you tube channel saying that the ISS is a fake , because they had a leek, and the station was not torn apart by the out side vacuum!
This is nonsense, the pressure difference is only one atmosphere , which I think is only fourteen pounds per square inch.
And the leek itself was only two millimeters across, it would have taken weeks to empty the station.
I think he'd been watching too many bad SF films!
 

psikeyhackr

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Another common misconception is that vacuums suck, they don't, it's the other way round, it's the surrounding air which rushes in to fill the vacuum!
But that is all suck ever did. People just suck at thinking about physics. LOL
 

Ray Pullar

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The ISS, which occupies a low orbit, is not in true vacuum. There is a trace of Earth's outer atmosphere. Skylab had an emergency tarp flung across her hull and this sheet flapped around in the breeze, as I recall from watching NASA footage. P.S. I agree that the leak in true vacuum would be slow for a small hole.
 
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BigBadBob141

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If people suck, as you say, at physics or maths, it's because they are taught poorly!
I think the ISS is about 250 miles above the earth, higher then Skylab maybe.
At this height any trace of atmosphere would very, very slight, more or less a hard vaccum!
As I say, am not sure what the height of Skylab was, look it up on wiki, but am sure there was no breeze.
Skylab did eventually lose orbit because of atmospheric friction, but this was very slight, there would be no detectable breeze.
Just like there is no breeze on the moon, yet the spring loaded flag there appeared to flap!
The reason they both flapped was because of weightlessness in Skylabs case, and low gravity in the moon's case.
Any motion the so called tarp ( it was a reflective cover, they weren't out camping) had or the flag, takes a long time to die down because of no atmosphere, therefore no friction!
 
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Ray Pullar

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Skylab was 269-274.6 miles high, greater than ISS. I saw the parasol shift about as a boy, wondered how with no air, found out later there was some.
 

Ray Pullar

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ISS, and Skylab before it, orbit well within the thermosphere of Earth's atmosphere which lies between 50 and 620 miles above sea-level.
 

BAYLOR

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Your mass remains the same, but your weight depends on the strength of the gravity field you are in.
You weigh less on the Moon and Mars because they are smaller then the Earth, and therefore have less mass, so less gravity!
If you could stand on the surface of the Sun or Jupiter you would be a hell of a lot heavier , your weight would be greater but your mass remains the same!
Another common misconception is that vacuums suck, they don't, it's the other way round, it's the surrounding air which rushes in to fill the vacuum!
There was a flat earther on a you tube channel saying that the ISS is a fake , because they had a leek, and the station was not torn apart by the out side vacuum!
This is nonsense, the pressure difference is only one atmosphere , which I think is only fourteen pounds per square inch.
And the leek itself was only two millimeters across, it would have taken weeks to empty the station.
I think he'd been watching too many bad SF films!
Lt Commnader Data said something to that effect in an episode of Star Trek The Next Generation.
 

BigBadBob141

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It has been discovered that the Earth's atmosphere extends beyond the Moon.
However at that distance the density is about 0.28 atoms per cubic centimeter!
Which is a bit on the thin side for breathing.
As I have been trying to point out, there may be faint traces of atmosphere at 250 miles above sea level, but it is so thin it may as well be regarded as a fairly hard vacum, there is no breeze, wind or anything remotely like that.
Eventually friction against these faint traces could bring the ISS out of orbit, but this would probably take a long time, and could be counter-acted by firing boosters, which I think the ISS does on a regular basis!
In fact it is very hard to say where our atmosphere ends and the solar atmosphere and winds begin!
 

Dave

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A "flapping" would not be due to wind as, already pointed out, there isn't the density of gas to hit anything. It would be more likely a vibration with a very long wave frequency. With almost no friction, once started it would have nothing to slow it down. Like those executive desk toys with the swinging balls that used to be popular.

And yes, Weight is a Force so it equals Mass x Acceleration (where the acceleration is due to gravity.) F = ma or in this case F=mg. That is GCSE Physics. Or it used to be.
 

Vertigo

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Yes there is almost no air friction but the material itself will resist movement and it would damp down quite quickly without any further agitation, which just happened to be provided by Skylab itself.

"flapping" of the sun shade was caused from the exhaust of the reaction
control subsystem (RCS) thrusters of the Skylab 3 CSM.


Taken from this: S73-34619. The pictures are no longer there but the text is enough.
 

BAYLOR

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The Star Trek Episode Obsession In this one they're are dealing with entity that can not only change its molecular structure composition but. can throw itself out time sync making it impossible to kill with any kind of weapon so ,phasers wouldn't hurt itand in theory even the antimatter explosion should have not have been able ot kill it. It was able able ot go though the ships defector should like they we're not even there. So it should all have been able to phase through the ships hull but instead the creature entesr the ship though an open impulse engine vent. and it when ig got into Ensign Garovicks quarters , they were able to reverse carbon pressure and suck it out though the vent. Given the creature nature and compassion, this too doesn't make any sense. All also ,how is it that the ships air ducts and ventilation system are somehow connected to the Starships impulse engine vents? :unsure:
 

Vertigo

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The Star Trek Episode Obsession In this one they're are dealing with entity that can not only change its molecular structure composition but. can throw itself out time sync making it impossible to kill with any kind of weapon so ,phasers wouldn't hurt itand in theory even the antimatter explosion should have not have been able ot kill it. It was able able ot go though the ships defector should like they we're not even there. So it should all have been able to phase through the ships hull but instead the creature entesr the ship though an open impulse engine vent. and it when ig got into Ensign Garovicks quarters , they were able to reverse carbon pressure and suck it out though the vent. Given the creature nature and compassion, this too doesn't make any sense. All also ,how is it that the ships air ducts and ventilation system are somehow connected to the Starships impulse engine vents? :unsure:
I confess I long since stopped expecting Star Trek, original in particular, to be too concerned with physical consistency!

PS: You appear to have suffered rather at the hands of auto correct/insert in that post. Think I figured it all out though! :D
 

BAYLOR

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I confess I long since stopped expecting Star Trek, original in particular, to be too concerned with physical consistency!

PS: You appear to have suffered rather at the hands of auto correct/insert in that post. Think I figured it all out though! :D
Im coming to the belief that the auto correct has a grudge against me. :D
 

BAYLOR

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And how much does 100 foot tall Gorilla like King Kong eat ? Im thinking King Kong on Skull Island would very quickly exhaust any food supplies there. :unsure:
 

Vertigo

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From extremely large beasts - to miniature people and incredible shrinking machines. They are literally incredible because they are impossible. it is pure fantasy.
Don't get me started on shrinking machines. If you're not going to lose complexity, ie. keep the same number of cells and therefore molecules, then you are going to have to somehow persuade atoms to get smaller. Yeah like that's going to happen. And if you do lose molecules/cells and so dodge the smaller atoms issue then good luck with any intelligence!
 
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